It is well known that polymers may be applied to the surfaces of fibers or fiber products in order to change and enhance the properties of the fibers or fiber products in a desired manner. In particular, in such procedures, the fibers are to be hydrophilized in order to increase the wear comfort of articles of clothing produced from them. Furthermore, the soiling of the textiles, their electrostatic charge and other use properties are to be improved.
German Patent No. 26 43 637 discloses a method for finishing fiber products containing cellulose fibers with a synthetic resin. In this method, the fiber products are treated with a solution or dispersion of a glycidyl-containing copolymer, whereupon the products are dried and then heat treated in the presence of an acid catalyst, the heating being effected to a temperature sufficient to split the oxiran bond of the glycidyl group. The catalyst is incorporated in the solution or dispersion of the copolymer or is applied before or after the drying step in the form of a separate solution or dispersion. The method is characterized in that a copolymer is used, which comprises:
(a) 1 to 55 mole percent of at least one structure unit of the formula: ##STR2## wherein
R.sub.1 is a hydrogen atom or a methyl group and Q is CO or CH.sub.2.
(b) 0.5 to 25 mole percent of at least one structure unit of the formula: ##STR3## wherein
R.sub.2 is a hydrogen atom or a methyl group;
R.sub.3 is a linear or branched alkylene group with not more than 3 carbon atoms:
R.sub.4 is a hydrogen atom, a linear or branched alkyl group, an acryloyl group or a methacryloyl group and
m is a whole number from 5 to 25 and
(c) 98.5 to 20 mole percent of at least one structure unit of the formula: ##STR4## wherein
R.sub.5 is a hydrogen atom or a methyl group and
R.sub.6 is a linear or branched alkyl group or a hydroxyalkyl group, as well as optionally
(d) up to 10 mole percent of other vinyl-like structure units.
In the German Offenlegungsschrift 3,244,011, a water-dispersible polyester is described, which is built up from components of formula EQU --CO--A--CO--G--O--
wherein
A represents, on the statistical average, 80 to 100 mole percent of p-phenylene and 0 to 20 mole percent of a bivalent group of the formula ##STR5##
and G represents, on the statistical average, 30 to 90 mole percent of linear or branched bivalent alkane groups with 3 to 6 carbon atoms, which may also be interrupted by 1 or 2 oxygen atoms, 10 to 30 mole percent of bivalent polyether groups with an average molecular weight of 1.000 to 3.000 and 0 to 50 mole percent of ethylene groups and R represents a linear or branched alkyl group or alkenyl group with 6 to 18 carbon atoms.
The dispersible polyester is intended to be used for the hydrophilization, the antistatic finishing and the soil release finishing of fiber materials, which consist completely or to a considerable extent of hydrophobic fibers.
However, the products used for the method of the German Pat. No. 2,643,637 have the disadvantage that the handle or "touch" of the textile material treated with them is undesirably hard. Moreover, the polymer on the fibers is saponified by the action of alkalis, so that the permanence, that is, the resistance to laundering of the finished textile material is insufficient.
Deficient permanence is also a disadvantage of a finish produced on the basis of a dispersible polyester of the German Offenlegungsschrift No. 3,244,011. This is due to the fact that the polyesters are not cross linked and can therefore easily be detached from the fibers by washing.
A material for the hydrophilic finishing of fibers or fiber products should fulfill the following conditions:
The wear comfort of the textiles should be increased owing to the fact that body moisture can be better dissipated through the fabric to the outside.
The finish should have the highest possible permanence and still have a hydrophilizing effect after a larger number of conventional washing processes.
The ability to soil the textiles should be reduced. It should also be easier to remove existing soil from the textiles.
Graying of white domestic laundry articles is to be reduced.
The electrostatic charge on the textiles should be diminished. The uptake of dust is also minimized in this manner.